Add 21/40 and 9/7
1st number: 21/40, 2nd number: 1 2/7
21/40 + 9/7 is 507/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 7 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Likewise, for the 2nd fraction, since 7 × 40 = 280,
9/7 = 9 × 40/7 × 40 = 360/280 - Add the two like fractions:
147/280 + 360/280 = 147 + 360/280 = 507/280 - So, 21/40 + 9/7 = 507/280
In mixed form: 1227/280
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